Myoglobinuria: evaluation of methods in the clinical diagnosis acute renal failure.

Patients with red--brown urine which may be a sign of myoglobinuria, can develop acute renal failure. We assayed serum creatinine, blood urea nitrogen (BUN) and creatine kinase activity in a total of 33 patients of equal groups, A (automobile accident), B (trauma) and C (undergoing rhabdomyolysis). In addition we tested 132 urine samples for the presence of myoglobin using a dipstick assay. Only five patients in group A showed any sign of myoglobinuria with increased creatine kinase activity upto 7 times the normal value but their serum creatinine level and BUN were within the normal range. In contrast, all 22 patients in group B and C showed myoglobinuria and above normal concentrations of serum creatinine and BUN, with significantly increased (p < 0.0001) creatine kinase activity upto 150 times the normal range. Four of the most seriously ill patients in group C developed acute renal failure. Supplementation of routine determinations of serum creatinine and BUN and serum creatine kinase activity with a rapid test for myoglobinuria provides an extra indication of impending renal dysfunction. It may be beneficial in the emergency management of these patients.